Loans and Allowance for Loan Losses, Loan Balances by Internal Credit Quality Indicator (Details) $ in Thousands	6 Months Ended
	Dec. 31, 2017 USD ($) Segment	Jun. 30, 2017 USD ($)
Financing Receivable, Recorded Investment [Line Items]
Number of segments within loan portfolio | Segment	4
Total gross loans	$ 674,435	$ 634,331
Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	656,430	626,864
Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	946	1,242
Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	11,305	555
Increase in loans	10,800
Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	5,754	5,670
Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	0	0
Loss [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	$ 0	0
Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan-to-value ratio	89.90%
Residential Real Estate [Member] | Residential Mortgage with Private Mortgage Insurance [Member]
Financing Receivable, Recorded Investment [Line Items]
Loan-to-value ratio	95.00%
Residential Real Estate [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	$ 252,015	245,331
Residential Real Estate [Member] | Residential Real Estate [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	248,721	242,592
Residential Real Estate [Member] | Residential Real Estate [Member] | Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	930	813
Residential Real Estate [Member] | Residential Real Estate [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	90	91
Residential Real Estate [Member] | Residential Real Estate [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	2,274	1,835
Residential Real Estate [Member] | Construction and Land [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	7,391	7,160
Residential Real Estate [Member] | Construction and Land [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	7,391	7,160
Residential Real Estate [Member] | Construction and Land [Member] | Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	0	0
Residential Real Estate [Member] | Construction and Land [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	0	0
Residential Real Estate [Member] | Construction and Land [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	0	0
Residential Real Estate [Member] | Multi-family [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	13,707	9,199
Residential Real Estate [Member] | Multi-family [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	12,866	9,110
Residential Real Estate [Member] | Multi-family [Member] | Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	0	0
Residential Real Estate [Member] | Multi-family [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	756	0
Residential Real Estate [Member] | Multi-family [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	85	89
Commercial Real Estate [Member] | Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	272,253	257,964
Commercial Real Estate [Member] | Real Estate [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	260,337	255,090
Commercial Real Estate [Member] | Real Estate [Member] | Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	0	419
Commercial Real Estate [Member] | Real Estate [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	10,217	404
Commercial Real Estate [Member] | Real Estate [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	1,699	2,051
Commercial Real Estate [Member] | Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	24,901	28,430
Commercial Real Estate [Member] | Construction [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	24,725	28,254
Commercial Real Estate [Member] | Construction [Member] | Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	0	0
Commercial Real Estate [Member] | Construction [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	0	0
Commercial Real Estate [Member] | Construction [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	176	176
Consumer Loan [Member] | Home Equity [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	21,090	21,076
Consumer Loan [Member] | Home Equity [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	20,433	20,858
Consumer Loan [Member] | Home Equity [Member] | Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	0	0
Consumer Loan [Member] | Home Equity [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	0	0
Consumer Loan [Member] | Home Equity [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	657	218
Consumer Loan [Member] | Consumer Installment [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	4,925	4,790
Consumer Loan [Member] | Consumer Installment [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	4,915	4,770
Consumer Loan [Member] | Consumer Installment [Member] | Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	0	10
Consumer Loan [Member] | Consumer Installment [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	0	0
Consumer Loan [Member] | Consumer Installment [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	10	10
Commercial Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	78,153	60,381
Commercial Loans [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	77,042	59,030
Commercial Loans [Member] | Watch [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	16	0
Commercial Loans [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	242	60
Commercial Loans [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Total gross loans	$ 853	$ 1,291